Systems, devices, and methods for coupling a prosthetic implant to a fenestrated body

ABSTRACT

Devices, systems, and methods for coupling a prosthetic implant to a fenestrated body are disclosed herein. In some embodiments, a branch stent graft is provided. The branch stent graft can include an engagement portion for engagement with an opening in a fenestrated body, such as a vessel wall or an aortic stent graft. The engagement portion of the branch stent graft can be coupled to the fenestrated body such that the branch stent graft can move, rotate or shift relative to the fenestrated body but such that axial movement of the branch stent graft is restricted and/or prevented.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of U.S. ProvisionalPatent Application Ser. No. 62/369,978, entitled “Systems, Devices, andMethods for Coupling a Prosthetic Implant to a Fenestrated Body,” filedAug. 2, 2016, the disclosure of which is hereby incorporated byreference in its entirety.

BACKGROUND

The embodiments described herein relate generally to prosthetic implantsand more particularly, to devices and methods for engaging a prostheticimplant, such as, for example, an branch vessel stent graft, within afenestration of a second prosthetic implant, such as, for example, anaortic stent graft.

Prosthetic devices are often implanted into, for example, diseasedportions of a patient to repair, support, stent, and/or otherwisefacilitate the proper function of those diseased portions. In someinstances, prosthetic devices such as stent grafts can be used to repairdiseased portions of a patient's vascular system. For example, aneurysmswithin a patient's vascular system generally involve the abnormalswelling or dilation of a blood vessel such as an artery, whichtypically weakens the wall of the blood vessel making it susceptible torupture. An abdominal aortic aneurysm (AAA) is a common type of aneurysmthat poses a serious health threat. A common way to treat AAA and othertypes of aneurysms is to place an endovascular stent graft in theaffected blood vessel such that the stent graft spans across (e.g.,traverses) and extends beyond the proximal and distal ends of thediseased portion of the vasculature. The stent graft can, thus, relinethe diseased vasculature, providing an alternate blood conduit thatisolates the aneurysm from the high-pressure flow of blood, therebyreducing or eliminating the risk of rupture. In other instances, aprosthetic device can be an implant and/or mechanism, which can providestructural or functional support to a diseased and/or defective portionof the body. In some instances, however, the arrangement of the anatomycan present challenges when attempting to place and/or secure aprosthetic device (including stent grafts or the like). Such challengescan result in misalignment and/or suboptimal configuration of theprosthetic device within the anatomy.

Minimally invasive endovascular repair using stent grafts is oftenpreferred to avoid the risks associated with traditional open surgicalrepair. However, these stent grafts can only be used when the graft canbe placed in a stable position without covering major branch vessels. Inthe cases of juxtarenal aneurysm where the dilation extends up to butdoes not involve the renal arteries, the proximal portion of the stentgraft needs to be secured to the aortic wall above the renal arteries,thereby blocking the openings to the renal arteries. Thus, patients withjuxtarenal aneurysms, which represent a significant proportion ofabdominal aortic aneurysm cases, are typically excluded fromendovascular treatment.

To allow for endovascular repair of a wider range of cases, surgeonssometimes cut openings in the stent graft body to accommodate specificbranch vessel origins, a process known as “fenestration”. Thus, forexample, in treating juxtarenal aneurysms using a procedure known asFenestrated Endovascular Aortic Repair (“FEVAR”), the fenestrations oropenings of an aortic stent graft are to be aligned with the branchvessels. Additional stent grafts (e.g., renal stents) can then be placedin the branch vessels and secured to the primary stent graft (e.g.,aortic stent graft) to limit movement of the primary stent grafts withinthe anatomy and ensure proper blood flow. Additionally, in some cases,an endovascular stent graft can be placed within one or more specificbranch vessels to further treat an aneurysm and/or to reinforce thebranch vessel in the region of the aneurysm.

SUMMARY

Devices, systems, and methods for coupling a prosthetic implant to afenestrated body are disclosed herein. In some embodiments, a branchstent graft is provided. The branch stent graft can include anengagement portion for engagement with an opening in a fenestrated body,such as a vessel wall or an aortic stent graft. The engagement portionof the branch stent graft can be coupled to the fenestrated body suchthat the branch stent graft can rotate or shift relative to thefenestrated body but such that axial movement of the branch stent graftis restricted and/or prevented.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of a diseased abdominal aorta according to anembodiment.

FIG. 2A is a portion of a stent graft according to an embodiment anddirectly after placement within the diseased abdominal aorta of FIG. 1.

FIG. 2B is a portion of the stent graft of FIG. 2A and placed within thediseased abdominal aorta of FIG. 1 and after a time of indwelling.

FIG. 3 is an illustration of at least a portion of a fenestrated stentgraft according to an embodiment.

FIG. 4 is an illustration of the portion of the fenestrated stent graftof FIG. 3 positioned, for example, within a portion of a diseasedabdominal aorta.

FIG. 5A is a schematic illustration of a front view of a fenestratedbody, according to an embodiment.

FIGS. 5B-5D are schematic illustrations of a side view of a system infirst configuration, a second configuration, and a third configuration,respectively, according to an embodiment.

FIG. 6 is a schematic illustration of a cross-sectional side view of asystem, according to an embodiment.

FIG. 7 is a schematic illustration of a cross-sectional side view of asystem, according to an embodiment.

FIG. 8 is a schematic illustration of a cross-sectional side view of asystem, according to an embodiment.

FIG. 9 is a schematic illustration of a cross-sectional side view of asystem, according to an embodiment.

FIG. 10 is a schematic illustration of a cross-sectional side view of asystem, according to an embodiment.

FIGS. 11A-11C are schematic illustrations of cross-sectional side viewsof a system in a first configuration, a second configuration, and athird configuration, respectively, according to an embodiment.

FIG. 12 is a schematic illustration of a cross-sectional side view of asystem, according to an embodiment.

FIG. 13A is a schematic illustration of a cross-sectional side view of asystem, according to an embodiment, in a first configuration.

FIG. 13B is a schematic illustration of a cross-sectional side view ofthe system of FIG. 13A in a second configuration.

FIG. 14 is a schematic illustration of a cross-sectional side view of asystem, according to an embodiment.

FIG. 15 is a schematic illustration of a cross-sectional side view of asystem, according to an embodiment.

FIG. 16A is a schematic illustration of a cross-sectional side view of asystem, according to an embodiment, in a first configuration.

FIG. 16B is a schematic illustration of a cross-sectional side view ofthe system of FIG. 16A in a second configuration.

FIG. 16C is a schematic illustration of a cross-sectional side view ofthe system of FIG. 16A in a third configuration.

FIG. 16D is a schematic illustration of a cross-sectional side view ofthe system of FIG. 16A in a fourth configuration.

FIG. 16E is a schematic illustration of an internal wall of the systemof 16D in the second configuration.

DETAILED DESCRIPTION

Devices, systems, and methods for coupling a prosthetic implant to afenestrated body are disclosed herein. In some embodiments, afenestrated body includes a flexible engagement portion. The prostheticimplant can be configured to engage with the flexible engagement portionsuch that the prosthetic implant can rotate relative to the fenestratedbody while maintaining a perpendicular angle between a longitudinalcentral axis of the prosthetic implant and a plane of the flexibleengagement portion.

In some embodiments, a branch stent graft is provided. The branch stentgraft can include an engagement portion for engagement with an openingin a fenestrated body, such as a vessel wall or an aortic stent graft.The engagement portion of the branch stent graft can be coupled to thefenestrated body such that the branch stent graft can rotate or shiftrelative to the fenestrated body but such that axial movement of thebranch stent graft is restricted and/or prevented.

As used in this specification, the singular forms “a,” “an” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, the term “a member” is intended to mean a singlemember or a combination of members, “a material” is intended to mean oneor more materials, or a combination thereof.

As used herein, the words “proximal” and “distal” refer to a directioncloser to and away from, respectively, an operator of, for example, amedical device. Thus, for example, the end of the medical devicecontacting the patient's body would be the distal end of the medicaldevice, while the end opposite the distal end would be the proximal endof the medical device. Similarly, when a device such as an endovascularstent graft is disposed within a portion of the patient, the end of thedevice closer to the patient's heart would be the proximal end, whilethe end opposite the proximal end would be the distal end. In otherwords, the proximal end of such a device can be upstream of the distalend of the device.

The embodiments described herein can be formed or constructed of one ormore biocompatible materials. Examples of suitable biocompatiblematerials include metals, ceramics, or polymers. Examples of suitablemetals include pharmaceutical grade stainless steel, gold, titanium,tungsten, nickel, iron, platinum, tin, chromium, copper, and/or alloysthereof. Examples of polymers include nylons, polyesters,polycarbonates, polyacrylates, polymers of ethylene-vinyl acetates andother acyl substituted cellulose acetates, non-degradable polyurethanes,polystyrenes, polyvinyl chloride, polyvinyl fluoride, poly(vinylimidazole), chlorosulphonate polyolefins, polyethylene oxide,polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE),urethanes, and/or blends and copolymers thereof.

The embodiments and methods described herein can be used to form apatient-specific prosthetic device and/or to facilitate the functionand/or the integration of the prosthetic device within a portion of apatient. For example, in some embodiments, the devices and/or methodsdescribed herein can be used in conjunction with and/or can otherwise beincluded in endovascular repair using stent grafts. Although theembodiments are shown and described herein as being used, for example,to facilitate endovascular repair, in other embodiments, any of thedevices and/or methods described herein can be used to facilitatetreatment of any portion of a patient. For example, the devices andmethods described herein can form and/or can facilitate the integrationof any suitable implant, prosthesis, device, mechanism, machine, and/orthe like within a portion of the body of a patient such as the patient'svascular system, nervous system, muscular-skeletal system, etc.Therefore, while some embodiments are shown and described herein asbeing used in the endovascular repair of an abdominal aortic aneurysm,they are presented by way of example and are not limited thereto.

Some of the devices and/or methods described herein can be used inminimally invasive treatment techniques such as endovascular repairusing stent grafts. Such repair techniques are generally preferred overtraditional open surgical repair and often result in reduced morbidityor mortality rates. In some instances, however, the arrangement of thediseased vasculature can result in a need to alter a portion of thestent graft prior to insertion into the body. For example, in anendovascular repair of an abdominal aortic aneurysm, the aneurysm can besituated adjacent to and/or directly distal to normally functioningvessels branching from a portion of the aorta. In order to reline theaneurysm with the stent graft, surgeons often cut openings in the stentgraft fabric to accommodate specific branch vessel origins, a processknown as “fenestration.” Specifically, in treating juxtarenal aneurysmsand/or when treating other aneurysms, shown in illustration in FIG. 1for instance, the fenestrations or openings of the stent grafts cancorrespond to a size, shape, and/or relative position of, inter alia,the renal arteries, the superior mesenteric artery (SMA), and/or theceliac artery (not shown in the illustration in FIG. 1).

Traditionally, the fenestration process involves measurements based onmedical images (such as CT scans) of the vessel origins. For example, insome instances, longitudinal distances of branch vessels can be measuredand relative angular locations of the branch vessels can be estimatedand/or calculated from a reference point. Based on these measurementsand/or calculations, a surgeon or manufacturer can mark and cut thestent fabric of a stent graft to define one or more fenestrations. Thefenestrated stent graft can then be positioned within the diseasedvasculature (e.g., via an endovascular procedure) and oriented tosubstantially align the fenestrations with openings of the correspondingbranch vessels.

In some instances, fenestrations in the fenestrated bodies (e.g.,fenestrated stent grafts or vessel walls) described herein can begenerated and/or otherwise formed based on medical imaging data of adiseased portion of a patient's vascular system (e.g., an abdominalaortic aneurysm). For example, an electronic device such as a personalcomputer, workstation, laptop, etc. can receive the imaging data and cancalculate and/or otherwise define a digital representation of theimaging data. Based on the digital representation, the electronic devicecan define one or more templates, process plans, instructions, datasets, and/or the like associated with and/or indicative of a desired setof fenestration locations along a body (e.g., a stent graft). In someinstances, the electronic device can output a map, plan, and/ortemplate, which in turn, can be used by a doctor, surgeon, technician,and/or manufacturer to form a fenestrated body (e.g. a fenestrated stentgraft). For example, in some embodiments, such a template or the likecan be substantially similar to those described in U.S. PatentPublication No. 2013/0296998 entitled, “Fenestration Template forEndovascular Repair of Aortic Aneurysms,” filed May 1, 2013 (“the '998publication”) and/or those described in U.S. patent application Ser. No.15/163,255 entitled, “Devices and Methods for Anatomic Mapping forProsthetic Implants,” filed May 24, 2016 (“the '255 application”), thedisclosures of which are incorporated herein by reference in theirentireties.

In other instances, fenestrations in the fenestrated bodies (e.g. afenestrated stent grafts or vessel walls) can be formed without suchtemplates. For example, in some embodiments, the electronic device canoutput instructions and/or code (e.g., machine code such as G-code orthe like) to a computerized numerical control (CNC) device and/or acomputer-aided manufacturing (CAM) device, which in turn, can performone or more manufacturing processes or the like associated with formingand/or otherwise marking fenestration locations along a patient-specificprosthesis (e.g., a stent graft). The formation of a patient-specificprosthesis can be performed in a manual process or in at least apartially automated process. Moreover, a change in the arrangement of aportion of the anatomy resulting from the insertion and/or indwelling ofthe prosthesis can be determined and/or calculated using the devicesand/or methods described in International Patent Application No.PCT/US2016/041355, entitled “Devices and Methods for Anatomic Mappingfor Prosthetic Implants,” filed Jul. 7, 2016 (“the '355 application”),the disclosure of which is incorporated herein by reference in itsentirety.

FIGS. 1-2B illustrate a diseased portion of a patient's abdominal aorta10. While portions of the abdominal aorta 10 are described below, thediscussion of the abdominal aorta 10 is not exhaustive; rather, thediscussion below provides a reference to the relevant anatomicstructures. Moreover, the discussion of the anatomic structures (e.g.,of the abdominal aorta 10) refers to the position, orientation, etc. ofsuch structures relative to the patient rather than as viewed by anobserver (e.g., a doctor). For example, when referring to a “left” sideof a patient or to anatomic structures disposed on or near the “left”side of the patient, “left” is intended to describe a position relativeto the patient and/or from the patient's perspective, as viewed in ananterior direction (e.g., forward)

The abdominal aorta 10 (also referred to herein as “aorta”) has aproximal end portion 11, receiving a flow of blood from the descendingaorta (not shown), and a distal end portion 12, supplying a flow ofblood to the lower limbs. As shown in FIG. 1, the aorta 10 at or nearthe proximal end portion 11 supplies a flow of blood to the right renalartery 13 and the left renal artery 14, which in turn, supply blood tothe right and left kidney (not shown), respectively. Although not shownin FIG. 1, the proximal end portion 11 of the aorta 10 also supplies aflow of blood to the superior mesenteric artery (SMA) and the celiacartery. The distal end portion 12 of the aorta 10 forms the iliacbifurcation 20, through which the aorta 10 supplies a flow of blood tothe right common iliac artery 15 and the left common iliac artery 16,which in turn, supply blood to the right and left lower limbs,respectively. As shown in FIG. 1, this patient has an abdominal aorticaneurysm (AAA) 17 positioned distal to the renal arteries 13 and 14 andproximal to the iliac bifurcation 20. More specifically, the AAA 17 isdisposed in a position that precludes the attachment of a proximal endportion of a stent graft between the renal arteries 13 and 14 and theAAA 17, and thus, a fenestrated stent graft 160 (se e.g., FIGS. 2A and2B) is used for endovascular repair of the AAA 17.

In some instances, endovascular repair of the AAA 17 includes scanningand/or otherwise capturing anatomic imaging data associated with thepatient's aorta 10. For example, an imaging device can be an X-raydevice, a computed tomography (CT) device, a computed axial tomography(CAT) device, a magnetic resonance imaging device (MRI), a magneticresonance angiogram (MRA) device, a positron emission tomography (PET)device, a single photon emission computed tomography (SPECT) device, anultrasound device, and/or any other suitable device for imaging aportion of the patient and/or a combination thereof (e.g., a CT/MRAdevice, a PET/CT device, a SPECT/CT device, etc.). The imaging datacaptured by the imaging device can thus, be used to determine salientfeatures of the patient's aorta 10 such as, for example, the branchvessels in fluid communication with the aorta 10. For example, a doctor,surgeon, technician, manufacturer, etc. can use the imaging data todetermine and/or calculate a size, shape, position, and/or orientationof the aorta 10, the branch vasculature in fluid communication with theaorta 10 (e.g., the renal arteries 13 and 14), and/or any other suitablevasculature or anatomic structure. In some instances, the doctor,surgeon, technician, manufacturer, etc. can form and/or define one ormore fenestrations 165 in the stent graft 160 associated with thedetermined and/or calculated characteristics of at least the renalarteries 13 and 14, as described in the '998 application, the '255application, and/or the '355 application, incorporated by referenceabove.

As shown in FIG. 2A, the stent graft 160 can be positioned within aportion of the patient's abdominal aorta 10 via an endovascularprocedure. For example, the stent graft 160 can be disposed within adelivery catheter (e.g., in a collapsed, compressed, restrained, and/orotherwise un-deployed configuration), which is inserted into, forexample, the femoral artery (not shown). The delivery catheter can beadvanced through the artery and into the abdominal aorta 10. Onceadvanced to a desired position within the abdominal aorta 10, thedelivery catheter can be withdrawn relative to the stent graft 160. Asthe delivery catheter is retracted and/or withdrawn, the stent graft 160transitions from the collapsed configuration to an expanded or deployedconfiguration, thereby stenting a portion of the abdominal aorta 10.

The stent graft 160 includes a proximal end portion 161 and a distal endportion 162 and defines a lumen therethrough 163. The stent graft 160can be any suitable stent graft. For example, the stent graft 160 can beformed from a resilient, biocompatible material such as those describedabove. For example, a stent graft can include a stent or framework towhich a graft material is coupled. In some embodiments, the stent (i.e.,framework) can be constructed from a metal or metal alloy such as, forexample, nickel titanium (nitinol) and the graft material can beconstructed from a woven polymer or fabric such as, for example,polytetrafluoroethylene (PTFE) or polyethylene terephthalate (PET orDacron®)). In some embodiments, the graft material or fabric can bewoven onto the stent and/or coupled to the stent in any other suitablemanner to form the stent graft (e.g., the stent graft 160).

The stent graft 160 also includes a set of stiffening members 164disposed circumferentially about the stent graft 160. The stiffeningmembers 164 can be any suitable structure that can, for example, biasthe stent graft 160 in an open configuration, thereby structurallysupporting the stent graft material (also known as “stent fabric” or“graft fabric”). In some embodiments, the stiffening members 164 can beformed from a metal or a metal alloy such as, for example, thosedescribed above. In some embodiments, such a metal or metal alloy, forexample, is radiopaque and/or otherwise coated with a radiopaquematerial configured to be visible using, for example, fluoroscopy. Thestiffening members 164 can transition from a restrained or deformeddelivery configuration (e.g., when disposed in a delivery catheter) toan expanded and/or biased indwelling configuration, as shown in FIG. 2A.

In this embodiment, the stent graft 160 defines the set of fenestrations165, as described above. As described herein, the position of thefenestrations 165 along the stent graft 160 can be based on anatomicimaging data and/or one or more digital representations of the patient'sanatomy. A doctor, surgeon, technician, and/or manufacturer can then usethe imaging data and/or digital representations to define thefenestrations 165 in the graft fabric. As shown, in this example, thefenestrations 165 are each aligned with its corresponding renal artery13 or 14 and can each have a size, shape, and/or configuration that isassociated with its corresponding renal artery 13 or 14. In this manner,the fenestrations 165 can allow blood to flow from the aorta 10 and intothe right renal artery 13 and the left renal artery 14 via thefenestrations 165. Although not shown in FIG. 2A, the stent graft 160can define one or more fenestrations associated with other branchvessels stemming from the aorta 10 such as, for example, the superiormesenteric artery (SMA), the celiac artery, and/or the like.

As shown in FIG. 2B, the placement and/or indwelling of the stent graft160 within the aorta 10 can, for example, alter, shift, rotate,translate, morph, and/or otherwise reconfigure the arrangement of thepatient's aorta 10. As a result, the openings of the renal arteries 13and 14 are shifted relative to the fenestrations 165 defined by thestent graft 160. In some instances, the shifting of the aorta 10relative to the stent graft 160 results in at least a partial blockageof the renal arteries 13 and 14, as shown in FIG. 2B. For example, insome instances, the openings of the renal arteries 13 and 14 can beabout 4 millimeters (mm) to about 7 mm, and the shifting and/orrearrangement of the aorta 10 can result in a shifting of the openingsof the renal arteries 13 and 14 relative to the fenestrations 165 byabout 1 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm,about 7 mm, or more (or fraction of a millimeter there between). Thus,despite defining the fenestrations 165 in desired positions along thestent graft 160 based on the imaging data, the shifting of the aorta 10resulting from the placement and/or indwelling of the stent graft 160can result in a blockage of the renal arteries 13 and 14. In someinstances, the shifting of the aorta 10 can result in about a 1%, 5%,10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100% (or any percent orfraction of a percent there between) blockage of the renal arteries 13and 14. Although not shown in FIGS. 2A and 2B, the shifting of the aorta10 can result in a similar misalignment of any branch vessel relative toits corresponding fenestration in the stent graft 160. In someembodiments, an electronic device can be configured to determine and/orcalculate the shift in the anatomy that would result from the insertionand/or indwelling of prosthesis (e.g., a stent graft) and can define oneor more digital representations of the shifted anatomy. One or morefenestrations can be formed in a stent graft (e.g., the stent graft 160)based on the calculated shift, as described in the '998 application, the'255 application, and/or the '355 application, incorporated by referenceabove.

FIG. 3 illustrates at least a portion of a fenestrated stent graft 260according to an embodiment. As described above, a stent graft can defineone or more fenestrations configured to accommodate one or more branchvessels when the stent graft is deployed in an aorta. Specifically, inthis embodiment, the fenestrated stent graft 260 includes a proximal endportion 261 and a distal end portion 262, and defines a lumen 263 and aset of fenestrations 265. The fenestrated stent graft 260 can be anysuitable stent graft and/or prosthesis. For example, in someembodiments, the fenestrated stent graft 260 can be an off-the-shelfstent graft. In other embodiments, the fenestrated stent graft 260 canbe a patient-specific stent graft with a size, shape, and/orconfiguration corresponding to the patient's anatomy.

The fenestrated stent graft 260 (also referred to herein as “stentgraft”) can have any suitable shape, size, and/or configuration. Forexample, in some embodiments, the stent graft 260 can have a size thatis associated with a size of the lumen defined by the aorta. In otherembodiments, the fenestrated stent graft 260 can have a size that isassociated with an adjusted or calculated size of the lumen defined bythe aorta resulting from the endovascular placement of the stent graft260. Moreover, the stent graft 260 can have any suitable mechanicalproperties such as, for example, strength, stiffness, etc.

As shown in FIG. 3, in some embodiments, the stent graft 260 can includestent 264 and a graft fabric 266. The stent 264 can be, for example, anysuitable stent and/or framework configured to increase a stiffness ofthe stent graft 260 and/or to provide structural support for the stentgraft 260. As described above, the stent 264 can be formed from anysuitable metal or metal alloy such as nitinol. In some embodiments, thestent 264 can be configured to transition between a first, expandedand/or implanted configuration and a second, collapsed, and/or deliveryconfiguration. Furthermore, in some instances, the stent 264 can bebiased such that the stent 264 is in the first configuration until aforce is exerted on the stent 264 to transition it from the firstconfiguration to the second configuration (e.g., when disposed in adelivery cannula or the like).

The graft fabric 266 can be formed from any suitable polymer or fabricsuch as, for example. Dacron® or the like. In some embodiments, thegraft fabric 266 can be woven around and/or through the stent 264. Inother embodiments, the graft fabric 266 can be coupled to the stent 264via sutures, a friction fit, or an adhesive, and/or can encapsulate thestent 264 between at least two layers of graft fabric 266. As shown inFIG. 3, the graft fabric 266 defines the fenestrations 265, which can bearranged relative to the stent 264 such that the fenestrations 265 donot overlap the stent 264. In other words, the fenestrations 265 can bearranged along the stent graft 260 such that one or more portions of thestent 264 do not span and/or otherwise traverse the fenestrations 265.In other embodiments, one or more portions of the stent 264 can spanand/or otherwise traverse the fenestration 265. Moreover, as describedin detail above, the fenestrations 265 can be defined by the graftfabric 266 at locations along the stent graft 260 based on an updated,projected, anticipated, and/or otherwise calculated digitalrepresentation of a portion of a patient's vasculature.

As described above, the stent graft 260 can be any suitable stent graftand can be formed via any suitable manufacturing process or processes.In some embodiments, the stent graft 260 can be manufactured as anoff-the-shelf stent graft and the fenestrations 265 can be formed in thegraft material 266 in a subsequent manufacturing process. In otherembodiments, the stent graft 260 can be manufactured as a “custom” ornot-off-the-shelf stent graft. While specific methods of manufacturingare described herein, it is to be understood that the methods arepresented by way of example only and not limitation. Moreover, themethods of manufacturing described herein can be performed at a singlefacility and/or in a single manufacturing process or can be performed atmultiple facilities and/or in multiple manufacturing processes. In someinstances, portions of the methods of manufacturing described herein canbe performed by an end user such as a doctor, surgeon, technician,nurse, etc. Thus, while the manufacturing of the stent graft 260 isspecifically described below, the stent graft 260 can be formed via anysuitable manufacturing process or processes and is not limited to thosediscussed herein.

In some instances, the stent graft 260 can be manufactured with ageneral shape, diameter, length, etc. associated with a patient's aortabased on, for example, calculations from anatomic imaging data of thepatient. In other embodiments, the stent graft 260 can have a generalshape, size, and/or configuration associated with the updated modeldefined by the electronic device, which in turn, corresponds to acalculated, projected, and/or modified arrangement of the aorta inresponse to the insertion and indwelling of, for example, the stentgraft 260, as described in detail above. Hence, a stent graft 260generally has a tubular or cylindrical shape. In some embodiments, thediameter of the lumen 263 is at least partially based on a diameter ofthe calculated, projected, and/or modified lumen defined by the aorta.Moreover, the stent graft 260 can have a stiffness and/or any othersuitable mechanical properties associated with an anticipated amountand/or method of shifting of the aorta resulting from the insertionand/or indwelling of the stent graft 260, as described in the '998application, the '255 application, and/or the '355 application,incorporated by reference above.

The fenestrations 265 can be defined along the stent graft 260 such thateach fenestration 265 corresponds to a calculated position of thecorresponding branch vasculature such as, for example, the renalarteries, and each fenestration 265 can be formed in any suitablemanner, as described in the '998 application, the '255 application,and/or the '355 application, incorporated by reference above.

As shown in FIG. 4, when the fenestrations 265 are defined along thestent graft 260, the stent graft 260 can be positioned within a portionof the patient's body using any suitable endovascular procedure. In thisembodiment, the stent graft 260 is positioned within the patient's aorta10. As shown, the stent graft 260 can include, for example, a first setof fenestrations 265A, which are associated with and/or otherwisecorrespond to the right renal artery 13 and the left renal artery 14.Specifically, each of the fenestrations 265A are aligned with itscorresponding renal artery 13 or 14 and can each have a size, shape,and/or configuration that is associated with its corresponding renalartery 13 or 14. In some embodiments, the size, shape, and/or positionof the fenestrations 265A is associated with and/or substantiallycorresponds to the adjusted and/or calculated size, shape, and/orposition of its corresponding renal artery 13 and 14. For example,placing the stent graft 260 within the aorta 10 can, for example, alter,shift, rotate, translate, morph, and/or otherwise reconfigure thearrangement of the patient's aorta 10. Thus, by basing the stent graft260 off of the updated model, the size, shape, and/or position of thefenestrations 265 defined by the stent graft 260 can correspond to thedesired branch vasculature (e.g., the right renal artery 13 and/or theleft renal artery 14). Moreover, in addition to positioning the stentgraft 260 within a portion of the patient's aorta 10, the renal arteries13 and/or 14 can also be stented, for example, through the fenestrations265A (not shown in FIG. 4). Stenting of the renal arteries can becarried out with secondary branch stents (not shown in FIG. 4) thatengage with the fenestrated body of the stent graft 260 at thefenestrations 265A and extend within branch arteries like the renalarteries 13 and/or 14. As such, the fenestrations 265A on the stentgraft 260 and the secondary branch stents (not shown) positioned tocorrespond to the branch arteries can help with the axial and/or radialalignment and positioning of the stent graft 260 during deployment.Further the fenestrations 265A and the secondary branch stents (notshown) can also help maintain the alignment and positioning of the stentgraft 260 relative to the patient's aorta 10 after placement.

As shown in FIGS. 3 and 4, in some embodiments, the stent graft 260 caninclude a second set of fenestrations 265B, which are associated withand/or otherwise correspond to other branch vessels that otherwise,might be blocked by an un-fenestrated portion of the stent graft 260.For example, the fenestrations 265B can be associated with and/orotherwise correspond to the superior mesenteric artery (SMA) 18 and theceliac artery 19, respectively. In other embodiments, the stent graft260 can define fenestrations to accommodate more or fewer branch vesselsthan illustrated here. For example, in some embodiments, the stent graft260 can define fenestrations to accommodate the inferior mesentericartery (IMA), internal iliac arteries, and/or the like. Thus, thefenestrations 265 defined by the stent graft 260 can allow blood to flowfrom the aorta 10 to the branch vasculature, which would otherwise beobstructed by the stent graft 260 material.

In some embodiments, the arrangement of the stent graft 260 and/or thepatient's aorta can be such that a fenestration 265 is partially definedby the stent graft 260. For example, as shown, the proximal mostfenestration 265B is disposed at the proximal end of the stent graft 260and corresponds to the celiac artery 19 that is partially covered by thegraft material during deployment. As such, the fenestration 265B for theceliac artery 19 is partially circular or U-shaped to accommodate theportion of the celiac artery 19 otherwise blocked by the graft material.In other embodiments, any of the fenestrations 265 can have non-circularand/or irregular shapes.

In some embodiments, the fenestrations 265 can be marked to facilitatelocation of the fenestrations 265 during deployment of the stent graft260 and to facilitate the coupling of branch stents (not shown) with thestent graft 260. For example, the peripheral edges 267A or 267B of thestent graft 260 that define the fenestrations 265A or 265B may besutured using gold wires and/or wires of other radiopaque materials.Similarly, the location of the fenestration 265 can be marked by one ormore radiopaque markers. Such radiopaque wires or markers can facilitatefluoroscopic visualization of the fenestrations 265 during anendovascular repair procedure and allow a physician to locate thefenestration 265 with respect to the corresponding branch vessel. Inother embodiments, the fenestrations 265 can be sutured and/or otherwisemarked using any suitable material that can increase visibility, forexample, when using any suitable imaging device (e.g., MRI scan, CATscan, PET scan, X-Ray scan, ultrasound, etc.). Such markers can beplaced and/or sutured in any suitable manufacturing process, which canbe combined with or separate from the formation of the fenestrations265.

As described above, in some embodiments, a secondary branch stent can becoupled within a fenestration (e.g., fenestrations 265) of a stent graft(e.g., stent graft 260). The relative position of the secondary branchstent can help in the axial and radial alignment and/or positioning ofthe stent graft 260 with respect to the patients aorta 10 duringdeployment. During placement of the stent graft the secondary stent canbe disposed within a branch vessel (e.g., the SMA 18) extending from apatient's aorta such that the secondary stent can aid in reinforcing thebranch vessel in an open position. Additionally, the secondary stent mayhelp maintain the axial and/or radial positioning of the stent graftrelative to the patient's aorta (e.g., aorta 10) after placement. Thesecondary stent may be movable within and/or relative to thefenestration such that a motion of the branch vessel can be accommodated(i.e., vessel tortuosity can be compensated for and vessel kinking canbe prevented). In some embodiments, a fenestrated body, such as a mainstent graft, can include a flexible portion surrounding a fenestrationsuch that a rigid branch stent engaged with the fenestrated body at thefenestration can rotate within the fenestration. For example, FIG. 5A isa schematic illustration of a front view of a fenestrated body 460. Thefenestrated body 460 can be, for example, a main stent graft, such as anaortic stent graft. The fenestrated body 460 can have the same orsimilar structure and/or function as any of the other fenestrated bodiesor stent grafts described herein, such as, for example, stent graft 160or stent graft 260. The fenestrated body 460 can define a fenestration465 and include an engagement portion 468 surrounding the fenestration465. The engagement portion 468 can be flexible and can be configured toengage with a branch stent graft 430 (shown in FIGS. 5B-5D). The branchstent graft 430 can be any suitable stent, such as, for example, abridge stent or a FEVAR stent.

FIGS. 5B-5D are schematic illustrations of a side view of a system 400in a first, second, and third configuration, respectively. The system400 includes the fenestrated body 460 and the branch stent graft 430.The branch stent graft 430 can be rigid or flexible. The engagementportion 468 can be configured such that a plane or face of theengagement portion 468 remains normal to a longitudinal central axis ofthe branch stent graft 430 as the branch stent graft 430 moves relativeto the fenestrated body 460 through the configurations shown in FIGS.5B-5D. As shown in FIG. 5B, the branch stent graft 430 can be positionedin the first configuration in which the longitudinal central axis of thebranch stent graft 430 is perpendicular to a wall of the fenestratedbody 460. As shown in FIG. 5C, the branch stent graft 430 can move to asecond position (i.e., the second configuration) relative to the branchstent graft 430. As shown in FIG. 5D, the branch stent graft 430 canmove to a third position (i.e., the third configuration) relative to thebranch stent graft 430. Although the system 400 is shown in FIGS. 5B-SDas having three configurations for illustrative purposes, the system 400can essentially have an infinite number of configurations. In otherwords, the engagement portion 468 is sufficiently flexible to allow thelongitudinal central axis of the branch stent graft 460 to remainaligned with the branch vessel regardless of movement of the fenestratedbody 460.

In some embodiments, the engagement portion 468 can include a flexiblelocking mechanism (not shown). The flexible locking mechanism can beconfigured to engage the branch stent graft 430 and maintain theengagement between the flexible locking mechanism and the branch stentgraft 430 through a variety of branch stent graft 430 positions. Theflexible locking mechanism can also restrict and/or prevent axialmovement of the branch stent graft 430 within and/or relative to thefenestration 465 of the fenestrated body 460.

In some embodiments, rather than the fenestrated body including flexibleengagement portion, an engagement portion of the fenestrated body can berigid and an associated branch stent graft can be flexible. For example,FIG. 6 is a schematic illustration of cross-sectional side view of asystem 500 that includes a fenestrated body 560 and a flexible branchstent graft 530. The branch stent graft 530 can be any suitable stent,such as, for example, a bridge stent or a FEVAR stent. The fenestratedbody 560 can be, for example, a main stent graft, such as an aorticstent graft. The fenestrated body 560 can have the same or similarstructure and/or function as any of the other fenestrated bodies orstent grafts described herein, such as, for example, stent graft 160 orstent graft 260. The fenestrated body 560 can define a fenestration 565and include a rigid engagement portion 568 surrounding the fenestration565. The engagement portion 568 can be substantially similar to thosedescribed in International Patent Application No. PCT/US2017/037157entitled, “Systems, Devices, and Methods for Marking and/or ReinforcingFenestrations in Prosthetic Implants” filed Jun. 13, 2017 (“the '157application”), the disclosure of which is incorporated herein byreference in its entirety.

The flexible branch stent graft 530 can include a proximal end 535 and adistal end 537. The rigid engagement portion 568 can be securely coupledto the proximal end 535 of the flexible branch stent graft 530. Thedistal end 537 of the flexible branch stent graft 530 can move freelydue to the flexibility of the branch stent graft 530. Factors that caninfluence the flexibility of the branch stent graft 530 can include, forexample, the stent pattern, the thickness of the stent material, thetype of stent material, and/or the type of connection between the branchstent graft 530 and another stent. The flexible branch stent graft 530can be moved from a first position to a second position, represented byflexible branch stent graft 530′. In the second position, the proximalend 535 of the flexible branch stent graft 530 remains securely coupledto the rigid engagement portion 568. The distal end 537′, however, isdisposed in a second position relative to the second end 537 and theflexible branch stent graft 530′ is bent into a different shape thanwhen in the first position. Due to the secure attachment between theproximal end 535 of the flexible branch stent graft 530 and the rigidengagement portion 568, the flexible branch stent graft 530 cannot moveaxially relative to the fenestration 565 and the fenestrated body 560.The secure attachment between the proximal end 535 of the flexiblebranch stent graft 530 and the rigid engagement portion 568 can beachieved by any suitable coupling structure. For example, the flexiblebranch stent graft 530 can include a ring with a flange on the proximalend 535.

The flange can be disposed in an abutting arrangement with a portion ofthe rigid engagement portion 568 facing the interior of the fenestratedbody 560. In other implementations, the proximal end 535 of the flexiblebranch stent graft 530 and the rigid engagement portion 568 can beengaged via a saddle feature, such as the saddle-shaped engagementportion 1031 described below.

In some embodiments, any suitable flexible branch stent graft can beconfigured to be securely coupled to an engagement portion of afenestrated body. For example, FIG. 7 is a schematic illustration ofcross-sectional side view of system 600 that includes a branch stentgraft 630 and a fenestrated body 660. The branch stent graft 630 can beany suitable stent, such as, for example, a bridge stent or a FEVARstent. The fenestrated body 660 can be, for example, a main stent graft,such as an aortic stent graft. The fenestrated body 660 can have thesame or similar structure and/or function as any of the otherfenestrated bodies or stent grafts described herein, such as, forexample, stent graft 160 or stent graft 260. The fenestrated body 660can define a fenestration 665 and include an engagement portion 668surrounding the fenestration 665. The engagement portion 668 can berigid or flexible and may be configured to be securely coupled to thebranch stent graft 630.

The branch stent graft 630 includes a first rigid stent portion 632 anda second rigid stent portion 634. The first rigid stent portion 632 andthe second rigid stent portion 634 are coupled by a flexible stentportion 636. Said another way, the flexible branch stent graft 630 canbe formed as a unitary stent with a constant, cylindrical outer diameterand can include portions with varying flexibilities or rigidities. Dueto the flexibility of the flexible stent portion 636, the branch stentgraft 630 can bend and/or rotate relative to the engagement portion 668.For example, the branch stent graft 630 can be bent from a firstposition in which a central axis of the branch stent graft 630 isperpendicular to a plane or face of the engagement portion 668 to asecond position represented by branch stent graft 630′ in which thebranch stent graft 630′ has a curved central axis. As shown, the secondrigid stent portion 634′ can be shifted to the second position while thefirst rigid stent portion 632′ remains securely coupled to and immobilerelative to the engagement portion 668. Additionally, the secureengagement between the first rigid stent portion 632′ and the engagementportion 668 can prevent axial movement of the branch stent graft 630relative to the fenestrated body 660.

In some embodiments, a first flexible stent portion and a secondflexible stent portion can be coupled by a rigid stent portion. Forexample, FIG. 8 is a schematic illustration of cross-sectional side viewof system 1200 that includes a branch stent graft 1230 and a fenestratedbody 1260. The branch stent graft 1230 can be any suitable stent, suchas, for example, a bridge stent or a FEVAR stent. The fenestrated body1260 can be, for example, a main stent graft, such as an aortic stentgraft. The fenestrated body 1260 can have the same or similar structureand/or function as any of the other fenestrated bodies or stent graftsdescribed herein, such as, for example, stent graft 160 or stent graft260. The fenestrated body 1260 can define a fenestration 1265 andinclude an engagement portion 1268 surrounding the fenestration 1265.The engagement portion 1268 can be rigid or flexible and may beconfigured to be securely coupled to the branch stent graft 1230.

The branch stent graft 1230 includes a first flexible stent portion 1232and a second flexible stent portion 1234. The first flexible stentportion 1232 and the second flexible stent portion 1234 are coupled by arigid stent portion 1236. Said another way, the branch stent graft 1230can be formed as a unitary stent with a constant, cylindrical outerdiameter and can include portions with varying flexibilities orrigidities. Due to the flexibility of the first flexible stent portion1232 and the second flexible stent portion 1234, the branch stent graft1230 can bend and/or rotate relative to the engagement portion 1268. Forexample, the branch stent graft 1230 can be bent from a first positionin which a central axis of the branch stent graft 1230 is perpendicularto a plane or face of the engagement portion 1268 to a second positionrepresented by branch stent graft 1230′ in which the branch stent graft1230′ has a varying central axis (i.e., the central axes of the firstflexible stent portion 1232 and the second flexible stent portion 1234are curved). As shown, the first flexible stent portion 1232′ and thesecond flexible stent portion 1234′ can be shifted to the secondposition where each have a second shape, while the rigid stent portion1236′ maintains the same shape in the second position. Additionally, thesecure engagement between the first flexible stent portion 1232′ and theengagement portion 1268 can prevent axial movement of the branch stentgraft 1230 relative to the fenestrated body 1260.

In some embodiments, a branch stent graft can include two rigid portionscoupled by a flexible tether. For example, FIG. 9 is a schematicillustration of a cross-sectional side view of a system 700 thatincludes a flexible branch stent graft 730 and a fenestrated body 760.The branch stent graft 730 can be any suitable stent, such as, forexample, a bridge stent or a FEVAR stent. The fenestrated body 760 canbe, for example, a main stent graft, such as an aortic stent graft. Thefenestrated body 760 can have the same or similar structure and/orfunction as any of the other fenestrated bodies or stent graftsdescribed herein, such as, for example, stent graft 160 or stent graft260. The fenestrated body 760 can define a fenestration 765 and includean engagement portion 768 surrounding the fenestration 765. Theengagement portion 768 can be rigid or flexible and may be configured tobe securely coupled to the branch stent graft 730.

The flexible branch stent graft 730 includes a first rigid stent portion732 and a second rigid stent portion 734. The first rigid stent portion732 and the second rigid stent portion 734 are coupled by a flexiblebar-like tether 736. The first rigid stent portion 732 and the secondrigid stent portion 734 can be the same or different sizes, lengths,and/or shapes. Due to the flexibility of the tether 736, the flexiblebranch stent graft 730 can bend and/or rotate relative to the engagementportion 768. For example, the flexible branch stent graft 730 can bebent from a first position in which a central axis of the flexiblebranch stent graft 730 (i.e. a central axis running through the firstrigid stent portion 732 and the second rigid stent portion 734) isperpendicular to a plane of the engagement portion 768 to a secondposition represented by flexible branch stent graft 730′ in which thetether 736′ is curved. As shown in FIG. 9, the second rigid stentportion 734′ can be shifted to the second position while the first rigidstent portion 732′ remains securely coupled to and immobile relative tothe engagement portion 768. Additionally, the secure engagement betweenthe first rigid stent portion 732 and the engagement portion 768 canprevent axial movement of the branch stent graft 730 relative to thefenestrated body 760.

In some embodiments, a branch stent graft can include a rigid portionand a flexible tail. For example, FIG. 10 is a schematic illustration ofcross-sectional side view of a system 800 that includes a branch stentgraft 830 and a fenestrated body 860. The branch stent graft 830 can beany suitable stent, such as, for example, a bridge stent or a FEVARstent. The fenestrated body 860 can be, for example, a main stent graft,such as an aortic stent graft. The fenestrated body 860 can have thesame or similar structure and/or function as any of the otherfenestrated bodies or stent grafts described herein, such as, forexample, stent graft 160 or stent graft 260. The fenestrated body 860can define a fenestration 865 and include an engagement portion 868surrounding the fenestration 865. The engagement portion 868 can berigid or flexible and can be configured to be coupled to the branchstent graft 830.

The flexible branch stent graft 830 includes a rigid stent portion 832,a flexible tail portion 836, and a flexible transition portion 833coupling the rigid stent portion 832 and the flexible tail portion 836.The flexible transition portion 833 can be less flexible than theflexible tail portion 836 such that the flexible transition portion 833can provide strain relief between the rigid stent portion 832 and theflexible tail portion 836, thus preventing a kink point or structuralfatigue between the rigid stent portion 832 and the flexible tailportion 836. Due to the flexibility of the flexible tail portion 836 andthe flexible transition portion 833, the flexible tail portion 836 canbend and/or rotate relative to the rigid stent portion 832 and theengagement portion 868. For example, the flexible tail portion 836 canbe bent from a first position in which a central axis of the branchstent graft 830 (i.e. a central axis running through the rigid stentportion 832, the flexible transition portion 833, and the flexible tailportion 836) is perpendicular to a plane of the engagement portion 868to a second position represented by branch stent graft 830′ in which theflexible tail portion 836′ is curved. As shown, the flexible tailportion 836′ can be shifted to the second position while the first rigidstent portion 832′ remains securely coupled to and immobile relative tothe engagement portion 868 due to the flexibility of the flexibletransition portion 833 and the flexible tail portion 836′. The flexibletail portion 836′ can be formed of any suitable material, such as, forexample, a metal or metal alloy such as, for example, nickel titanium(nitinol), stainless steel, or cobalt-chromium, and/or a woven polymeror fabric such as, for example, polytetrafluoroethylene (PTFE) orpolyethylene terephthalate (PET or Dacron®). Additionally, the secureengagement between the rigid stent portion 832 and the engagementportion 868 can prevent axial movement of the branch stent graft 830relative to the fenestrated body 860.

In some embodiments, a branch stent graft can be configured to movablyengage with an engagement portion of a fenestration body. For example,in some embodiments, both an engagement portion of a fenestrated bodyand an engagement portion of a branch stent graft can be rigid. Theengagement portion of the fenestrated body and the engagement portion ofthe branch stent graft can engage and/or interlock such that the branchstent graft can move and/or rotate relative to the fenestrated body. Forexample, FIGS. 11A-11C are schematic illustrations of cross-sectionalside views of a system 900 that includes a branch stent graft 930 and afenestrated body 960. The branch stent graft 930 can be any suitablestent, such as, for example, a bridge stent or a FEVAR stent. Thefenestrated body 960 can be, for example, a vessel wall or a main stentgraft, such as an aortic stent graft. The fenestrated body 960 can havethe same or similar structure and/or function as any of the otherfenestrated bodies or stent grafts described herein, such as, forexample, stent graft 160 or stent graft 260. The fenestrated body 960can define a fenestration 965 and include a rigid engagement portion 968surrounding the fenestration 965. The rigid engagement portion 968 canbe configured to be coupled to the branch stent graft 930. In someembodiments, the rigid engagement portion 968 includes a reinforcedand/or marked edge of the wall of the fenestrated body 960 in the regionsurrounding the fenestration 965. In other embodiments, the rigidengagement portion 968 includes the wall of the fenestrated body 960 inthe region surrounding the fenestration 965 and is not reinforced.

The branch stent graft 930 can include an engagement portion (not shown)configured to movably couple the branch stent graft 930 to theengagement portion 968 of the fenestrated body 960. Due to theengagement portion of the branch stent graft 930 being movably coupledto the engagement portion 968 of the fenestrated body 960, the branchstent graft 930 can move, pivot, and/or rotate relative to thefenestrated body 960, as shown in FIGS. 11A-11C. Specifically, as shownin FIG. 11A, the branch stent graft 930 can be configured in a firstposition relative to the fenestrated body 960 such that a central axisof the branch stent graft 930 is perpendicular to a central axis of thefenestrated body 960. The branch stent graft 930 can move relative tothe fenestrated body 960 such that the branch stent graft 930 is in asecond position relative to the fenestrated body 960, as shown in FIG.11B. The branch stent graft 930 can move relative to the fenestratedbody 960 into a third position relative to the main stent graft 960, asshown in FIG. 11C. Additionally, the engagement between the engagementportion of the branch stent graft 930 and the engagement portion 968 ofthe fenestrated body 960 can restrict or prevent axial movement of thebranch stent graft 930 relative to the fenestrated body 960.

In some embodiments, an engagement portion of a branch stent graft canbe formed in any suitable shape. For example, FIG. 12 is a schematicillustration of a cross-sectional side view of a system 1000 thatincludes a branch stent graft 1030 and a fenestrated body 1060. Thebranch stent graft 1030 can be any suitable stent, such as, for example,a bridge stent or a FEVAR stent. The fenestrated body 1060 can be, forexample, a vessel wall or a main stent graft, such as an aortic stentgraft. The fenestrated body 1060 can have the same or similar structureand/or function as any of the other fenestrated bodies or stent graftsdescribed herein, such as, for example, stent graft 160 or stent graft260. The fenestrated body 1060 can define a fenestration 1065 andinclude an engagement portion 1068 surrounding the fenestration 1065.The engagement portion 1068 can be configured to be coupled to thebranch stent graft 1030. In some embodiments, the engagement portion1068 includes a reinforced and/or marked edge of the wall of thefenestrated body 1060 in the region surrounding the fenestration 1065.In other embodiments, the engagement portion 1068 includes the wall ofthe fenestrated body 1060 in the region surrounding the fenestration1065 and is not reinforced.

The branch stent graft 1030 can include a saddle-shaped engagementportion 1031. The saddle-shaped engagement portion 1031 is configured tobe movably coupled to the engagement portion 1068 of the fenestratedbody 1060. In some embodiments, the branch stent graft 1030 can beself-expanding. For example, the saddle-shaped engagement portion 1031can be collapsible and have a biased-expanded shape such that the branchstent graft 1030 can be collapsed for delivery and insertion through thefenestration 1065. Upon being positioned within the fenestration 1065such that the saddle-shaped engagement portion 1031 is aligned with theengagement portion 1068 of the fenestrated body 1060, the saddle-shapedengagement portion 1031 can be deployed such that the saddle-shapedengagement portion 1031 automatically assumes an expanded configurationand engages with the engagement portion 1068 of the fenestrated body1060, as shown in FIG. 12.

In other embodiments, the engagement portion 1031 or the entire branchstent graft 1030 can be moldable and radially expandable. A separateexpandable member, such as a balloon, can be used to expand and/or shapethe branch stent graft 1030 after the branch stent graft 1030 has beendelivered to the target location relative to the engagement portion 1068of the fenestrated body 1060. The expandable member can be expanded suchthat the engagement portion 1031 of the branch stent graft 1030 isshaped via the force the expandable member applies to the inner surfaceof the engagement portion 1031. In some embodiments, the expandablemember can be pre-shaped such that the unconstrained, expanded shape ofthe expandable member includes two larger diameter portions separated bya smaller diameter portion (e.g., an hourglass shape). The pre-shapedexpandable member can apply pressure to the inner surface of theengagement portion 1031 such that the engagement portion 1031 takes asimilar shape. In other embodiments, the expandable member can have anunconstrained, cylindrical expanded shape, and the expandable member canbe limited in expansion by the engagement portion 1068 of thefenestrated body 1060 such that the expandable member can only expand oneither side of the engagement portion 1068. As a result, the expandablemember can only apply expansion force to the inner surface of theengagement portion 1031 on either side of the engagement portion 1068,causing the engagement portion 1031 of the branch stent graft 1030 to beshaped as shown in FIG. 12. The expandable member can be compliant ornon-compliant.

In some embodiments, the system 1000 can include a stop feature suchthat the user can determine when the engagement portion 1031 of thebranch stent graft 1030 and the engagement portion 1068 of thefenestrated body 1060 are appropriately aligned for deployment and/orexpansion of the engagement portion 1031. The stop feature can belocated on a delivery device used to deliver the branch stent graft1030, on the engagement portion 1068, and/or on the engagement portion1031. In some embodiments, the stop feature can be located on anexpandable member, such as a balloon, that is used to expand and/orshape the branch stent graft 1030. For example, when the expandablemember is in a first expanded configuration, the stop feature can engagean anatomical feature, such as the aorta wall, such that a user isalerted that the expandable member is properly located. The expandablemember can then be moved to a second expanded configuration to applypressure to the inner surface of the engagement portion 1031 such thatthe engagement portion 1031 is forced into the desired shape. In someembodiments, radiopaque markers, such as, for example, bands, can bedisposed on the branch stent graft 1030 and/or the engagement portion1068 such that the relative positions of the branch stent graft 1030 andthe engagement portion 1068 can be visually confirmed before deploymentand/or expansion of the engagement portion 1031.

When the saddle-shaped engagement portion 1031 is engaged with theengagement portion 1068 of the fenestrated body 1060, the branch stentgraft 1030 can move pivotally or rotationally relative to the engagementportion 1068 of the fenestrated body 1060. The saddle-shaped engagementportion 1031 can include a flared distal end to restrict or preventaxial movement of the branch stent graft 1030 relative to thefenestrated body 1060 while still allowing movement (e.g., pivotal,rotational, etc.) relative to the fenestrated body 1060.

In some embodiments, the saddle-shaped engagement portion of a branchstent graft can have any suitable shape. For example, FIG. 13A is aschematic illustration of a cross-sectional side view of a system 1100that includes a branch stent graft 1130 and a fenestrated body 1160. Thebranch stent graft 1130 can be any suitable stent, such as, for example,a bridge stent or a FEVAR stent. The fenestrated body 1160 can be, forexample, a vessel wall or a main stent graft, such as an aortic stentgraft. The fenestrated body 1160 can have the same or similar structureand/or function as any of the other fenestrated bodies or stent graftsdescribed herein, such as, for example, stent graft 160 or stent graft260. The fenestrated body 1160 can define a fenestration 1165 andinclude an engagement portion 1168 surrounding the fenestration 1165.The engagement portion 1168 can be configured to be coupled to thebranch stent graft 1130. In some embodiments, the engagement portion1168 includes a reinforced and/or marked edge of the wall of thefenestrated body 1160 in the region surrounding the fenestration 1165.In other embodiments, the engagement portion 1168 includes the wall ofthe fenestrated body 1160 in the region surrounding the fenestration1165 and is not reinforced.

The branch stent graft 1130 can include a saddle-shaped or an hour-glassshaped engagement portion 1131. The saddle-shaped engagement portion1031 is configured to be rotatably coupled to the engagement portion1168 of the fenestrated body 1160. In such a configuration, the branchstent graft 1130 can move relative to the engagement portion 1168 of thefenestrated body 1160.

In some embodiments, the engagement portion 1131 can be moldable and anexpandable member can be used to shape the engagement portion 1131. Asshown in FIG. 13A, the system 1100 can include an expandable member1140. The expandable member 1140 can be fluidically coupled to a fluidsupply mechanism (not shown) that can be controlled during deployment.After the engagement portion 1131 is positioned within the fenestration1165, the expandable member 1140 can be inserted into the fenestration1165 and aligned with the engagement portion 1131 of the branch stentgraft 1130 and the engagement portion 1168 of the fenestrated body 1160.The expandable member 1140 can then be expanded by, for example, usingthe fluid supply mechanism coupled to the expandable member, such thatthe engagement portion 1131 of the branch stent graft 1130 is shaped viathe force the expandable member 1140 applies to the inner surface of theengagement portion 1131.

In some embodiments, the expandable member 1140 can be pre-shaped suchthat the unconstrained, expanded shape of the expandable member 1140includes a first portion proximal to the fenestrated body 1160 and asecond portion 1144 distal to the fenestrated body 1160. The proximalportion further includes a first large diameter portion 1141, a secondsmaller diameter portion 1142 distal to the first large diameter portion1141, and a third larger diameter portion 1143 distal to the secondsmaller diameter portion 1142, as shown in FIG. 13A. The first, second,and third diameter portions of the first proximal portion form asaddle-shape or an hourglass shape of the expandable member 1140. Thefirst diameter of portion 1141 may be comparable or slightly larger orslightly smaller than the diameter of the third diameter of portion1143. The second small diameter portion 1142 forms the valley portionthat engages with the engagement portion 1168 of the fenestrated body1160.

The distal portion 1144 of the expandable member 1140 can be configuredto have a smaller diameter than the proximal portion containing thesaddle-shape. Further, the distal portion 1140 can be configured toengage with the tail portion 1136 of the branch stent graft 1130 uponexpansion, by applying expansion force to the inner side of the branchstent graft. Thus the distal portion 1144 of the pre-shaped expandablemember 1140 can cause the tail portion 1136 of the branch stent graft1130 to adopt a desired shape. Similarly, the proximal portion of theexpandable member 1140 can apply expansion force to the inner side ofthe proximal regions of the branch stent graft 1130 to cause the branchstent graft to assume a desired shape.

The proximal portion of the expandable member 1140 (including the first1141, second 1142, and third diameter 1143 portions) and the distalportion 1144 of the expandable member 1140 can be fluidically coupled toa single fluid supply mechanism or be separately connected to distinctfluid supply mechanisms to control their expansion during deployment.The pre-shaped expandable member 1140 can be used to apply pressure tothe inner surface of the engagement portion 1131 such that theengagement portion 1131 takes a similar shape.

In some embodiments, the expandable member 1140 can be semi-compliant.In some embodiments, the proximal portion of the expandable member 1140including the first 1141, second, 1142, and the third 1143 diameterportions forming the saddle-shape can be semi-compliant and the distalportion of the expandable member 1140 can be non-compliant. In someembodiments, the proximal and the distal portions can both be compliant,with the proximal portion having greater compliance than the distalportion of the expandable member 1140. In some embodiments, the distalportion can have a substantially comparable compliance or greatercompliance than the proximal portion of the expandable member 1140.

As described above, rather than including a flared proximal end whenfully expanded like the saddle-shaped engagement portion 1031 shown inFIG. 12, the saddle-shaped engagement portion 1131, upon expansion, caninclude two larger diameter portions connected by a smaller diametervalley portion. The engagement portion 1168 of the fenestrated body 1160can engage with the valley portion such that the two larger diameterportions prevent the branch stent graft 1130 from being moved axiallyaway from the main stent graft 1160 while still allowing rotationalmovement relative to the main stent graft 1160.

In some embodiments, the saddle-shaped engagement portion 1131 whenexpanded may be shaped such that the third diameter portion has a largerdiameter than the first diameter portion, while both the first and thethird portion have a larger diameter than the second portion that formsthe valley portion for engagement with the fenestrated body 1160. Insome other embodiments, the third diameter portion may have a smallerdiameter than the first portion and a larger diameter than the secondvalley portion that still is configured to engage with the fenestratedbody 1160 and prevent axial movement of the branch stent graft 1130,upon expansion

In some other embodiments, the first and third portions of thesaddle-shaped engagement portion 1131, when fully expanded, may havesubstantially equal diameter while the second portion has a smallerdiameter and engages with the fenestrated body 1160 to prevent axialmovement of the branch stent graft 1130 while allowing pivotal orrotational movement of the branch stent graft about the fenestrated body1160.

In some embodiments, the saddle-shaped engagement portion of the branchstent graft 1130 and the engagement portion 1168 of the fenestrated body1160 can be configured such that upon deployment the distal portion ofthe branch stent 1130 (including, for example, the third diameterportion of the saddle-shaped engagement portion 1131) is disposedoutside the fenestrated body 1160 and the proximal portion of branchstent (including, for example, the first diameter portion of thesaddle-shaped engagement portion 1131) is disposed inside thefenestrated body 1160. Further, the intermediate portion (for example,the second diameter portion of the saddle-shaped engagement portion 1131forming the valley portion) can be configured to be frictionally engageor engage through an interference fit with the opening or fenestrationin the engagement portion of the fenestrated body 1160.

In some embodiments, rather than using an expandable member, thesaddle-shaped engagement portion 1131 can be collapsible and have abiased-expanded shape such that the branch stent graft 1130 can becollapsed for delivery and insertion through the fenestration 1165. Uponbeing positioned within the fenestration 1165 such that thesaddle-shaped engagement portion 1131 is aligned with the engagementportion 1168 of the fenestrated body 1160, the saddle-shaped engagementportion 1131 can be deployed such that the saddle-shaped engagementportion 1131 assumes an expanded configuration (e.g., the configurationshown in FIG. 13B) and engages with the engagement portion 1168 of thefenestrated body 1160.

In some embodiments, the system 1100 can include a stop feature suchthat the user can determine when the engagement portion 1131 of thebranch stent graft 1130 and the engagement portion 1168 of thefenestrated body 1160 are appropriately aligned for deployment and/orexpansion of the engagement portion 1131. The stop feature can belocated on a delivery device used to deliver the branch stent graft1130, on the engagement portion 1168, and/or on the engagement portion1131. In some embodiments, the stop feature can be located on theexpandable member 1140. For example, when the expandable member 1140 isin a first expanded configuration, the stop feature can engage ananatomical feature, such as the aorta wall, such that a user is alertedthat the expandable member 1140 is properly located. The expandablemember 1140 can then be moved to a second expanded configuration toapply pressure to the inner surface of the engagement portion 1131 suchthat the engagement portion 1131 is forced into the desired shape. Insome embodiments, radiopaque markers, such as, for example, bands, canbe disposed on the branch stent graft 1130 and/or the engagement portion1168 such that the relative positions of the branch stent graft 1130 andthe engagement portion 1168 can be visually confirmed before deploymentand/or expansion of the engagement portion 1131.

As described above, the system 1300 in FIG. 14 can be substantiallysimilar to other systems described herein. For example, the system 1300can be similar to the system 500 illustrated in FIG. 6, or to the system600 illustrated in FIG. 7, or the system 800 illustrated in FIG. 10. Asan example, the branch stent graft 1130 can be substantially similar tothe branch stent 630 and the fenestrated body 1160 can be substantiallysimilar to the fenestrated body 660. Additionally, the engagementportion 1131 of the branch stent 1130 can be suitably rigid or flexibleto engage with the fenestrated body 1160 at the engagement portion 1168.The engagement portion 1131 of branch stent 1130 can include atransition portion 1133 and a distal tail portion 1136 defining alongitudinal central axis. Additionally, the branch stent 1130 can besuitably flexible or rigid to couple with the fenestrated body 1160 andmaintain the longitudinal central axis substantially perpendicular tothe plane defined by the opening in the fenestrated body 1160.

In some embodiments, the branch stent 1130 can include a tail portion1136 that is configured to have a flexibility greater than theflexibility of the engagement portion. For example, the flexibility ofthe tail portion can be 25% greater than the flexibility of theengagement portion 1131 of the branch stent graft 1130. In some otherembodiments, the flexibility of the tail portion may be comparable to orlesser than the flexibility of the engagement portion 1131.

In some embodiments, the tail portion 1136 of the branch stent graft1130 can include a cover 1138 made of a suitable material of suitablethickness and having a strain capability to impart the desiredflexibility to the branch stent 1130 and allow the branch stent graft toexpand. For example, the cover 1138 may be formed of one or more layersof a suitable material with a suitable microstructure such that theflexibility of the branch stent graft 1130 can be precisely controlled.As an example, the cover 1138 can be configured to have a straincapability to support expansion of the branch stent from a firstdiametrical size (e.g. about 2 mm) to a second substantially expandeddiametrical size (e.g. about 4-12 mm) with no failure. That is, thestrain capability of the cover 1138 can be designed to withstand abranch stent expansion in the example ranges of 2 mm-4 mm to 2 mm-12 mm.In some embodiments, the cover can have strain capability of at leastabout two times, at least about three times, at least about four times,or at least about five times the diametrical expansion of the engagementportion without experiencing a failure (e.g., a rip, a tear, etc.).

In some embodiments, the cover 1138 described above can be disposed overthe flexible tail portion 1136, the engagement portion 1131, thetransition portion, or any combination thereof. In other words, thecover can be disposed over any individual portion of the branch stentgraft 1130, multiple portions, or the entire branch stent graft 1130.Further, the cover 1138 disposed over the engagement portion 1131,transition portion 1133, and/or the tail portion 1136 of the branchstent graft 1130 can be configured to impart the desired flexibility toeach of the engagement, transition, and tail portions of the branchstent 1130. For example, the cover disposed over one or more of theportions described above can be of a suitable material with a suitablemicrostructure, and can be made suitably thick with a suitable number oflayers to render the desired flexibility with substantially precisecontrol.

The transition portion of the branch stent 1130 can be suitably flexibleor rigid to prevent any kink formation or structural fatigue between thefenestrated body 1160 and the branch stent 1130. For example, in someembodiments, the flexibility of the transition portion 1133 of thebranch stent 1130 can be greater than the flexibility of the engagementportion 1131 and less than the flexibility of the flexible tail portionof the branch stent 1130. In other words, the tail portion 1136 can beconfigured to be substantially more flexible than the transition portion1133 as well as the engagement portion 1131. For example, theflexibility of the tail portion 1136 of the branch stent 1130 can beconfigured such that the branch stent 1130 deflects from itslongitudinal axis by at least about 1 mm, at least about 2 mm, at leastabout 3 mm, or at least about 4 mm at a longitudinal distance of 20 mmaway from the engagement portion 1131 of the branch stent, when adeflecting force of less than 1 N is used. Said another way, theflexible tail portion defines a longitudinal central axis in a first,unstressed state, and is configured to deflect to a second, stressedstate when a deflecting force of less than about 1 N is applied at alongitudinal distance 20 mm away from the engagement portion. When sucha deflection force is applied, the flexible tail portion moves at leastabout 1 mm, at least about 2 mm, at least about 3 mm, or at least about4 mm from the first state to the second state. In some otherembodiments, the transition portion 1133 can be configured to have aflexibility comparable to or lesser than the engagement portion 1131and/or the tail portion of the branch stent 1130.

FIG. 14 is a schematic illustration of a cross-sectional side view of asystem 1300 including another shape of a branch stent graft 1330,according to an embodiment. As shown in FIG. 14, the system 1300includes the branch stent graft 1330 and a fenestrated body 1360. Thebranch stent graft 1330 can be any suitable stent, such as, for example,a bridge stent or a FEVAR stent. The fenestrated body 1360 can be, forexample, a vessel wall or a main stent graft, such as an aortic stentgraft. The fenestrated body 1360 can have the same or similar structureand/or function as any of the other fenestrated bodies or stent graftsdescribed herein, such as, for example, stent graft 160 or stent graft260. The fenestrated body 1360 can define a fenestration 1365 andinclude an engagement portion 1368 surrounding the fenestration 1365.The engagement portion 1368 can be configured to be coupled to thebranch stent graft 1330. In some embodiments, the engagement portion1368 includes a reinforced and/or marked edge of the wall of thefenestrated body 1360 in the region surrounding the fenestration 1365.In other embodiments, the engagement portion 1368 includes the wall ofthe fenestrated body 1360 in the region surrounding the fenestration1365 and is not reinforced.

The branch stent graft 1330 can include an engagement portion 1331. Theengagement portion 1331 can include a first larger diameter position1331A and a second larger diameter portion 1331B. The engagement portion1331 can be coupled to the engagement portion 1368 of the fenestratedbody 1360 such that the engagement portion 1368 of the fenestrated body1360 is positioned between the first larger diameter portion 1331A andthe second larger diameter portion 1331B. Thus, the branch stent graft1330 can move relative to the engagement portion 1368 of the fenestratedbody 1360. The first larger diameter portion 1331A and the second largerdiameter portion 1331B can each be a larger diameter than the diameterof the fenestration 1365 defined by the engagement portion 1368 of thefenestrated body 1360, thus restricting or preventing axial movement ofthe branch stent graft 1330 with respect to the main stent graft 1360while still allowing rotational and/or pivotal movement relative to themain stent graft 1360. Although the first larger diameter portion 1331Ais shown as being smaller in size than the second larger diameterportion 1331B, in some embodiments the first larger diameter portion1331A can be the same size as or a larger size that the second largerdiameter portion 1331B.

FIG. 15 is a schematic illustration of a cross-sectional side view of asystem 1400. The system 1400 includes a branch stent graft 1430 having adouble-sided engagement portion 1431. The system 1400 also includes afenestrated body 1460. The branch stent graft 1430 can be any suitablestent, such as, for example, a bridge stent or a FEVAR stent. Thefenestrated body 1460 can be, for example, a vessel wall or a main stentgraft, such as an aortic stent graft. The fenestrated body 1460 can havethe same or similar structure and/or function as any of the otherfenestrated bodies or stent grafts described herein, such as, forexample, stent graft 160 or stent graft 260. The fenestrated body 1460can define a fenestration 1465 and include an engagement portion 1468surrounding the fenestration 1465. The engagement portion 1468 can beconfigured to be coupled to the branch stent graft 1430. In someembodiments, the engagement portion 1468 includes a reinforced and/ormarked edge of the wall of the fenestrated body 1460 in the regionsurrounding the fenestration 1465. In other embodiments, the engagementportion 1468 includes the wall of the fenestrated body 1460 in theregion surrounding the fenestration 1465 and is not reinforced.

The double-sided engagement portion 1431 is configured to be movablycoupled to the engagement portion 1468 of the fenestrated body 1460. Theengagement portion 1431 of the branch stent graft 1430 includes a firstengagement feature 1431A and a second engagement feature 1431B. Theengagement portion 1431 (and thus, the first engagement feature 1431Aand the second engagement feature 1431B) can be any suitable shapecapable of engaging the engagement portion 1468 from the inside and/orthe outside of the fenestrated body 1460. For example, in someimplementations, the first engagement feature 1431A and the secondengagement feature 1431B can be structured and attached to thefenestrated body 1460 in a similar manner to a patent foramen ovale(PFO) closure device with a stent attached.

In some implementations, the first engagement feature 1431A and thesecond engagement feature 1431B can each be formed as expandable ringsand disposed on either side of the engagement portion 1468. The firstengagement feature 1431A can be positioned on a first side of theengagement portion 1468 (e.g., inside the fenestrated body 1460). Thesecond engagement feature 1431B can be positioned on a second side ofthe engagement portion 1468 opposite the first side (e.g. outside thefenestrated body 1460). The engagement portion 1431 can be coupled tothe engagement portion 1468 of the main stent graft 1460 such that theengagement portion 1468 of the fenestrated body 1460 is movably securedbetween the first engagement feature 1431A on the first side and thesecond engagement feature 1431B on the second side. In such aconfiguration, the branch stent graft 1430 can rotate and/or shiftrelative to the engagement portion 1468 of the fenestrated body 1460.The diameter of the first engagement feature 1431A and the secondengagement feature 1431B can be larger than the diameter of thefenestration defined by the engagement portion 1468, thus preventing thebranch stent graft 1430 from moving axially away from the fenestratedbody 1460 while still allowing rotational movement relative to thefenestrated body 1460.

In some implementations, the engagement portion 1431 of the branch stentgraft 1430 includes an X-shaped saddle such that the first engagementfeature 1431A includes a first prong element and a second prong elementand the second engagement feature 1431B includes a third prong elementand a fourth prong element. The first prong element and the second prongelement can be positioned on a first side of the engagement portion 1468(e.g., inside the fenestrated body 1460). The third prong element andthe fourth prong element can be positioned on a second side of theengagement portion 1468 opposite the first side (e.g. outside thefenestrated body 1460). The engagement portion 1431 can be coupled tothe engagement portion 1468 of the main stent graft 1460 such that theengagement portion 1468 of the fenestrated body 1460 is movably securedbetween the first prong element and the third prong element on the firstside and between the second prong element and the fourth prong elementon the second side. In such a configuration, the branch stent graft 1430can rotate and/or shift relative to the engagement portion 1468 of thefenestrated body 1460. A distance between the first prong element andthe second prong element and a distance between the third prong elementand the fourth prong element can be larger than the diameter of thefenestration defined by the engagement portion 1468, thus preventing thebranch stent graft 1430 from moving axially away from the fenestratedbody 1460 while still allowing rotational movement relative to thefenestrated body 1460.

In some embodiments, a branch stent graft can include an anchoringmember for engagement with an internal wall of a fenestrated body, suchas a main stent graft or a vessel wall. For example, FIGS. 16A-16E areschematic illustrations of various views and configurations of a system1500. The system 1500 includes a branch stent graft 1530 including ananchoring member 1550 and a fenestrated body 1560. The branch stentgraft 1530 can be any suitable stent, such as, for example, a bridgestent or a FEVAR stent. The fenestrated body 1560 can be, for example, avessel wall or a main stent graft, such as an aortic stent graft. Thefenestrated body 1560 can have the same or similar structure and/orfunction as any of the other fenestrated bodies or stent graftsdescribed herein, such as, for example, stent graft 160 or stent graft260. The fenestrated body 1560 can define a fenestration 1565 andinclude an engagement portion 1568 surrounding the fenestration 1565.The engagement portion 1568 can be configured to be coupled to thebranch stent graft 1530. In some embodiments, the engagement portion1568 includes a reinforced and/or marked edge of the wall of thefenestrated body 1560 in the region surrounding the fenestration 1565.In other embodiments, the engagement portion 1568 includes the wall ofthe fenestrated body 1560 in the region surrounding the fenestration1565 and is not reinforced.

The anchoring member 1550 can be in the form of a parachute or a flaredend portion of the branch stent graft 1530. The anchoring member 1550can be movable from a collapsed, delivery configuration to an expanded,anchoring configuration. As shown in FIG. 16A, which is a schematicillustration of a cross-sectional side view of the system 1500 in afirst configuration, the anchoring member 1550 can be delivered to thefenestration 1565 in the collapsed, delivery configuration. In someembodiments, the anchoring member 1550 can be delivered to thefenestration within a delivery tube (not shown). The anchoring member1550 can be biased toward the expanded configuration such that theanchoring member 1550 can be compressed within the delivery tube andthen automatically moved to the expanded configuration upon beingremoved from the delivery tube. As shown in FIG. 16B, which is aschematic illustration of a cross-sectional side view of the system 1500in a second configuration, the anchoring member 1550 can expand to theexpanded, anchoring configuration after, for example, being deliveredfrom an end of the delivery tube. Once the anchoring member 1550 isdeployed to the expanded, anchoring configuration, the anchoring member1550 can be positioned against the internal surface of the wall of thefenestrated body 1560 such that the anchoring member 1550 is engagedwith the engagement portion 1568 of the fenestrated body 1560 (e.g. suchthat the anchoring member 1550 abuts the engagement portion 1568) asshown in FIG. 16C. In such a configuration, the branch stent graft 1530can be positioned such that the branch stent graft 1530 extends throughthe fenestration 1565 but cannot move axially relative to thefenestration 1530. As shown in FIG. 16D, once the anchoring member 1550is positioned in an engaged relationship with the engagement portion1568, the branch stent graft 1530 can be expanded, such as via anexpandable member (e.g., a balloon), within the fenestration 1565. FIG.16E is a schematic illustration of the internal wall of the fenestratedbody 1560 with the anchoring member 1550 secured to the engagementportion 1568 of the fenestrated body 1560. In some embodiments, theanchoring member 1550 and the branch stent graft 1530 can be attached tothe fenestrated body in a similar manner to a patent foramen ovale (PFO)closure device with a stent attached.

Although only one anchoring member 1550 is shown in FIGS. 16A-16E, insome embodiments, a second anchoring member could be included such thatthe second anchoring member engages the outside wall of the fenestratedbody 1560. For example, a self-expanding parachute can be disposed onthe branch stent graft 1530 such that a first self-expanding parachutecan open on the inside of the fenestrated body 1560 and a secondself-expanding parachute can open on the outside of the fenestrated body1560, securing the branch stent graft 1530 to the fenestrated body 1560.

In use, as described above, the branch stent graft 1530 can be deliveredto a target location using a deployment device. For example, the branchstent graft 1530 can be delivered over a guidewire through thefenestrated body 1560, and out the fenestration 1565 of the fenestratedbody 1560 into a branch artery (not shown in FIGS. 16A-16E). In someimplementations, a delivery tube can be used to position the branchstent graft 1530 such that the anchoring member 1550 is within a lumenof the fenestrated body 1560 and another portion of the branch stentgraft 1530 is within a branch artery (similar to the configuration shownin FIG. 16A). In this position, the anchoring member 1550 (e.g., aparachute) can be deployed (similar to the configuration shown in FIG.16B). For example, the anchoring member 1550 or the entire branch stentgraft 1530 can be pushed out of an end of the delivery tube andautomatically expand to the configuration shown in FIG. 16B. Theanchoring member 1550 can then be pushed toward the fenestration 1530such that the anchoring member 1550 abuts the area of the fenestratedbody surrounding the fenestration (e.g., the engagement portion 1568, asshown in FIG. 16C). With the anchoring member abutting the wall and/orthe engagement portion of the fenestrated body, the branch stent graft1530 can be axially expanded within the fenestration 1565 and the branchartery (as shown in the configuration shown in FIG. 16D). For example,an expandable member (e.g., a balloon) can be inserted into a lumen ofthe branch stent graft 1530 and expanded, thus causing the branch stentgraft 1530 to expand to a wider-diameter configuration within thefenestration 1565.

While various embodiments of the system, methods and devices have beendescribed above, it should be understood that they have been presentedby way of example only, and not limitation. Where methods and stepsdescribed above indicate certain events occurring in certain order,those of ordinary skill in the art having the benefit of this disclosurewould recognize that the ordering of certain steps may be modified andsuch modifications are in accordance with the variations of theinvention. Additionally, certain of the steps may be performedconcurrently in a parallel process when possible, as well as performedsequentially as described above. The embodiments have been particularlyshown and described, but it will be understood that various changes inform and details may be made.

For example, although various embodiments have been described as havingparticular features and/or combinations of components, other embodimentsare possible having any combination or sub-combination of any featuresand/or components from any of the embodiments described herein inaddition, the specific configurations of the various components can alsobe varied. For example, the size and specific shape of the variouscomponents can be different than the embodiments shown, while stillproviding the functions as described herein.

1. A radially expandable branch stent graft assembly, comprising: anengagement portion for engaging with an opening in fenestrated body, theengagement portion configured to allow the branch stent graft to pivotabout the opening of the fenestrated body and to limit axial movement ofthe branch stent graft relative to the fenestrated body; and a flexibletail portion extending from the engagement portion.
 2. The branch stentgraft assembly of claim 1, wherein the engagement portion includes aproximal portion having a first diameter, an intermediate portion havinga second diameter, and a distal portion having a third diameter, thesecond diameter less than the first diameter and the third diameter inan expanded state.
 3. The branch stent graft assembly of claim 2,wherein the proximal portion is configured to be disposed on an insideof the fenestrated body, the distal portion is configured to be disposedon an outside of the fenestrated body, and the intermediate portion isconfigured to frictionally engage with the opening of the fenestratedbody.
 4. The branch stent graft assembly of claim 1, wherein theengagement portion is rigid.
 5. The branch stent graft assembly of claim1, wherein the engagement portion is flexible.
 6. The branch stent graftassembly of claim 1, further comprising: a transition portion disposedbetween the engagement portion and the flexible tail portion.
 7. Thebranch stent graft assembly of claim 6, wherein the engagement portionand the transition portion define a longitudinal central axis, theengagement portion configured to maintain the longitudinal central axissubstantially perpendicular to a plane defined by the opening in thefenestrated body.
 8. The branch stent graft assembly of claim 6, whereinthe transition portion is rigid.
 9. The branch stent graft assembly ofclaim 6, wherein the transition portion is flexible.
 10. The branchstent graft assembly of claim 1, wherein the flexibility of the flexibletail portion is imparted by at least one of a stent pattern, a stentthickness, and a stent material.
 11. The branch stent graft assembly ofclaim 1, wherein at least a portion of the flexible tail has a cover.12. The branch stent graft assembly of claim 11, wherein the flexibilityof the flexible tail portion is controlled by at least one of a coverthickness, a cover material, a cover microstructure, and a number oflayers of covering.
 13. The branch stent graft assembly of claim 11,wherein the cover has a strain capability of at least about five timesdiametrical expansion of the engagement portion.
 14. The branch stentgraft assembly of claim 1, wherein the flexible tail portion has aflexibility at least about 25% greater than the engagement portion. 15.The branch stent graft assembly of claim 1, wherein the flexible tailportion defines a longitudinal central axis in a first state, theflexible tail portion configured to deflect from the first state to asecond state when a deflecting force of less than about 1 N is applied.16. The branch stent graft assembly of claim 15, wherein the flexibletail portion is configured to move at least about 3 mm at a longitudinaldistance of 20 mm away from the engagement portion.
 17. The branch stentgraft assembly of claim 6, wherein the transition portion has aflexibility greater than the engagement portion and less than theflexible tail portion.
 18. A radially expandable branch stent graftassembly, comprising: a saddle-shaped engagement portion for engagingwith an opening in a fenestrated body, the saddle-shaped engagementportion including a proximal portion configured to be disposed on aninside of the fenestrated body, a distal portion configured to bedisposed on an outside of the fenestrated body, and an intermediateportion configured to frictionally engage with the opening offenestrated body.
 19. The branch stent graft assembly of claim 18,wherein the first portion has a first diameter, the intermediate portionhas a second diameter, and the distal portion has a third diameter, thesecond diameter less than the first diameter and the third diameter inan expanded state.
 20. The branch stent graft assembly of claim 19,wherein the first diameter is substantially equal to the third diameterin the expanded state. 21-35. (canceled)